Railway-traffic-controlling apparatus



May, 4 1926.-

-- 'R; A. M cANN v RAILWAY. TRAFFIC CONTROLLING APPARATUS Original Filed April 23, 1919 INVENTORZ u i W ML a-am #3 ATTOIIQNEY Patented May 4,'

'nonnnna. MoCANN, on sWIssvALii, mimmvmm; assrenon' ro 'i ir'n' Union SWITCH & SIGNAL oomrnmr; on swissvnnn,"PnimsYLvANIA, A CORPORATION r OF PENNSYLVANIA.

'RAILWAY-Timer:ooo'nTnoniime ArPAnATUs.

Substitute for application Serial no. esaiaajfiia April 23, 1915. This application filed July, as, i924;

To all whom it may concern: 7

Be it known that L Rosalind-r. MCCANN, a-citizen of the United States, residing at V Swissvale, i i-the county of Allegheny and State 10f Pennsylvania, have invented certain new and useful lniproveineiitsin Rail:

' ner that ,it flows 'in the sainedirection in? the two rails.

, apparatus-torfiuse;in systems. of the character set forth 1 V r In one system ofthe type mentioned, it hasecen proposed to einploy the usual track jcirciiit ci'iri'ent, thatis thecui'rent which energizes the track relays as one of the cur rents 'forjcontroliing the train vcarried zip-1' v paratus, and to supply another current. (which I will term the line 'current) to] therails ofeach .traclzsect-ion in such inanlVhen-this is. done, it will be seen thatwhen a track sectionis occu. pied by a train, it the lineflcurrent is of sufficient finagnitude and ofpropen phase, and it it'is sufficiently unbalancedpin the two track rails iii-the rear of the-train f in caus'eithe track relay for such section;

to become energized, thus c'a ti'sing a false, proceed signalin the rear-of the train. I One object of my invention istheproi'n sion of means for, inin'iediately opening. the circuit for the line. currentfOr-a'tracl; section in the erent that such current causes 'GIIQTg'iZZitlOD of the track relay when the section is occupi'ed,-- thus preventing a false proceed signal lll tll il lfll" of thetrain.

Another objecti ofiiny invention 'iswthe provision of means tor open-ingthe linecir} cuit'for a track section in'the"event that the signal for the next section in advancev sticks in' a proceed position while the latter section: 18 occupied-by a car or tram,

w I" will describe one form oftrackwayzcin v cults and apparatus :einbodying inyiinvein out; the i' ovelrf eati oin and will then point t-ures thereof in; claims-n fseinaphoi'ef type,

- Sri aFNo. 728,485. Y

".lhe accoinpanying' d 'awing is a diagramniaticview showing one forin of trackwaycircuits and apparatus embodying my invention.

Referring to the drawing the reference characters 2, 2 designate the two track rails ot a railway; along which l 'lilillo normallyn'ioves n the Clll'QClllOll ,indicated by the arrow. The-rails are divided, by insulatedt joints 3, intoafpluralityj oil-sections or blocks, or wh ch one complete section Gel) is shown in the, drawing except that the apparatus for ,seotionCD the sole function y or which is tofcontrol traffic signals and ind cations in the section to the left of polnt a't'ullunderstanding of the invention described herein. It is understood,however,

is omitted to si n'plity the-drawing,such

that a co nplete systein embodying -1ny'in- 'ventioii will usually comprise a plurality of successive sections each of which is equipped with; apparatus similar to 1 that shown in section C-Dj p e V 7} Located adjacent the entranceiend of section CD is a roadside signal s of the which signal indicates ste caution -;or -.proceed according as theseinaph'ore is inthe horizontal; inclined orrertical position. A similar signals? is irvovidecl for the section immediately to the The section C-D is provided witlra track circuit :coii'iprisiiig asource of alternating v s" at the exit and-entrance endsof the sect on, respectively. interposed betweentransfoi'iner T {and one A reactance 70 is rail of the section Relay H comprises; the 7 winding which I will terinthe track windin ;,-a second or local winding 5, .a

rotor responsiveto currents displaced in phase llitllHt-WO windings,"andcontacts '18, '34: and 9ioperated bycthe rotor. The local winding 5 is supplied, as hereinafter ex planned, with alternating current ofthe sanie frequency as that supplied to the primary oftransformer-T, but, displaced in phase from the current in] winding 4 by substantially 909. i 5

7 Signal} Sii's provided. with a caution ciri Cull? andia' proceed circ'u'itl Thecautionicircuit is from one'terminal B of a suitable source of-current through contact 8 of relay E, wire 18, and the operating mechanism of ,signaltd to the other terminal O oi the same source of current. It will be seen that this circuit is closed only when relay H is energized. The proceed circuit for signal S is from terminal B at signal S) througii contact of track relay H for the section to the right of section CD, wire 16, contact 3 y Set 01' rela- Y H wire 17 and IDBCi'lttlllSlH or signal S to terminal 0. g It will be seen that this-circuit is closed only when relays H and H are both ener 'ized.

The stator winding 5 of relay H is provided witha circuit which passes troni one terminal B of a suitable source of alternat ing current of the same frequency as that supplied co-transformer '1, through contact 7 of relay H, wires ltl'and- 11, and. winding 5 to the other terminal 6 of the same source of alternating current. This Winding is provided with a second circuit which passes from terminal 13* of thesame source of alterna-ting current througha contact 13 operated by signal S and closed only when the signal is at stop, wires 14 and 11, winding 5 to terminal 0 l'l llldlng 5 is energized,

; then, when relay H is open, provided. that signal S is at stop.v y

The actual sources from which current is supplied to signal S and winding 5 oi relay H are omitted from the drawing in or der to simplify the same as far as possible, the terminals of these sources being represented by the letters B, B, etc. and O, 0

It is understood, however, that in some instances one source only may be employed, in

which cases the points B, 15"]3 and B will" all be connected with one terminal otthe source, and points 0 and 0 will beconnected with the other terminal of such source; v The operation of the apparatus, in so far as the control or" signal S isiconcerned, is as follows:

Vrhen the track section C-D and the; sec tion next to the right are unoccupied, re

lays H and H are both energized, so that signal S indicates proceed. It then acar or train enters section CD. it causes relay H to become Clo-energ zed, thereby opening 7 the, control circuits for signal S at contacts 34, so that this signal moves tothe stop position. Relay winding 5 becomes deenergized by'the opening of relay contact 7,

but as soon as signal S moves to the stop position, this winding becomes energized again by virtue of the circuit passing through contact 13. As soon as the entire car or train-has passed out of section 6+1),

7 track relav H becomes energized thereb closing the caution circuit for signal S giso that this signal moves to the caution position. Contact 13 opens as soon as 'thesignal leaves the'stop position, but this has no ettrain enters section C+D, rovided t feet on winding 5 because the circuit including contact 7 is now closed. When the entire car oi-train has passed out jot, the section to theright of section (if-D, relay H closes. whereupon; signal s ams to" caution position, the patho't the line current is from transformer-ll, through pole changer l, wire 19, contact 25, operated by signal S wire 20, contact 21 0f relay H wire 22 to the middle point of an impedance 2?, thence through the two track rails 2 and 2 in multiple to a second impedance 28, from the middle point of which the current flows through wires 31 and 83, back contact f rel-a; U wires 32 and 24, and pole changer P to transformer U. The current'thus supplied is of what I will term ;norinal relative polarity. V] hen, however, signal S is in the stop position. contact 251s reversed,

"so that'wire 19 is disconnected from wire 20 and is connected with a. wire 23 which .36; the linecur'rent is then supplied to the track rails between impedances 36 and'28 only, and-owing to the fact that pole. changer P is then reversed, the current is it; will I be seen, then, that one or the other otthe then o Frevers e relative polarity.

circuits just traced will be closed when a lay H opens. In the event that this should' tick in the closed position due to'a mechanical detect, however, it is desirable that line curr nt be supplied to the rails to avoid stopping the trainyto do this, I provide the circuit for the line current with which branch isqtroin wire 31, through wire30,-

branch around relay contact 9,

signal operatedcontact 12, and'wire 29 to wire 2 l. Contact 12 is closed when signal S indicates proceed and caution, but open when the signal ind cates-stop. 'By virtue oi": this branch, :the line circuit is closed when signal S indicates proceed or caution, even though relay contact 9 is open.

Before proceeding further, it should be pointed out that the trackway apparatus hereshown is intended for co-operation with train carried governing apparatus in the following manner:dWhen the train is on a portion'ot track which is supplied with track- ClICttl'fi current and also with l ne current of leads to the middle point of an impedance relay 7 normal relative polarity, thegoverning apl paratus permits the train to travel at high firesa But when the train enters a portion of track from which the supply of either track circuit current or line current has been discontinned, the governing apparatus prevents the train from proceeding at more than a low speed, such as miles per hour. One

form of governing apparatus which will operate in thisina-nner with the trackway apparatus shown herein, is illustrated and described in Letters Patent of the United States No. 1,351,991, granted on the Tth-da-y of September, 1920, to'Lloyd V. Lewis, for

'railway trafiic controlling apparatus. Assum ng now that section CD is-occu 'pied by a car or train, it lS' conceivable that owing to a difierence in thel'resistances of the two lines of track rails the line current in the rear of the train may be sufficiently unbalanced in the two rails to cause track relay H to. become energized, it-being remembered that winding 5 is energized through contact 13 because signal S is at stop.. If this .happens,the relay will openat contact 9 the circuit for the line current, and

move more than a few degrees away from the stop position, however, because of contact 13. That is, if relay H remains closed long enough tocause signal S to nove, or if this signal should move due to the intermiuent closure of the relay, contactll3 will open and so will prevent furtherenergiza tion of relay H until this contact again closes. The car'or train which is in section CD is intermittently deprived of line current, and so it may be compelled to proceed' at a low speed, but it is'protected by a stop signal in its rear. As'soon. as the entire car circuit currentis againlsupplied to winding 7 H and circuits embodying my invention, it is or train passes out oztsection C- -D, track 4 of relay H so that this relay becomes energized and so causes signal S to move to the:

caution position. The oircuit'for winding ,5

" which includes contact 13 becomes opened as soon as the signalleaves the stop position,

7 but the. other circuit for this winding is then closed at contact.7, so that relay H continues to be, energized. Y

It will be noted that the circuit for the line current is normally closed when signal s indicates caution or proceed, but that this circuit isopened in the event that track relay H becomes energized by line current while the section CD is occupied by a car fications may be made therein within the scope of the appended claimswithout departing from the spirit and scope of my iiivention. i

I claim is entrain, provided thatsignal S Qis at the stop position.

in Should also be observed that wlien a train enters sectiOnCF-D,thetrack relay H willbje deene'rgized' regardless of unbalancing of the line current in the track rails, be-

cause the train then forms ashunt'd irectly across the terminals of windingtofthis relay, y

I will nowassunie that a train enters section C-D, thus opening relay H, and that winding ief this relay becomes energized by line current before signal S i'eaches the stop position. Relay H will not becoine'en-ei'gized to close its front contacts untilsignal S reaches its stop position because winding 5 is de-energized until that tiinez'; It follows, then, that contact 12 mustbe'opened before relay 'H c'a1ibecon-ie energized-due to line current, so that-it is iinpossible'for the relay to, be held'energized with the signal in 'cau tionoriproceed positiondueto the fiowot li-i1e current through contact 12.

It'will be-noted that the circuitfor the line current, when signal S -is in the proceed or caution position, passes through contact 21 of relay H The reasonfor this is as follows: Signal S is, of course, controlled by relay H and'is supposed to move to the stop position when relay H opens. But if this signal should stick in the proceed or caution position when a train enters the section to theright of CD,- then (neglecting contact 21 for the moment), line current would stillbe supplied torth'e' rails of secfl tion throughout the entire section, iiistead of toonly that portion of the section between}iinpedances 36' and 28 as should be the case. But with contaot'21 insertedbe tween wires 20 and 22, it will be seen thatit signal S should stickat caution or proceed when rela opens, the line circuit will be opened at contact 21 andso section C D will be'deprived completely of line current.

They present application is for the same invention as an earlier application filed by me v'ratus; I H a V Although I have herein shown and described-only one form oftrackway apparatus understood that various changes and modi- Having thus describedmyinveiition, what- 1. In combination, a sectio i ofrailway track, a track relay having a track winding tion controlled by said track relay, a circuit for the local winding of said track relay including a front contact of the relay, a branch for-said local winding circuit around said relay contact and including a contact which is closed or open according as said signal indicates stop or proceed, and a line circuit including the two rails of said section in multiple and having two branches one of which is closed or open according as said signal indicates proceed or stop and the other of which is closed oropen according as said relay is de-cnergized or energized;

2. In combination, a section of railway track, a track relay having a track winding and a local winding, a track circuit including said track winding and a source of current both of which are connected across the rails of said section, a signal. for said section controlled by. said track relay, means for supplying current to the local winding of said track relay when the signal indicates stop and for subsequently continuing the energization of said local winding when the,

relay is energized irrespective of the indication given by the signal, and-a line circuit including the two rails of said section in multiple and having two branches one of which is closed or open accorcing as said signal indicates proceed or stopand the other of which is closed or open according as said relay is de-energized or energized.

3. In combination, a section of railway track, a track relay having a track winding and a local winding, a track circuit including said track winding and 'a sourceof current both of which are connected across the railsof said section, asignal for said section controlled by said track relay, means for supplying current to the local winding of said track relay when the si nal indicates stop and for subsequently continuing the energization of said local winding when the relay is energized irrespective of the indication given by the signal, and a line circuit including the two rails of said section in multiple and controlled by a back contact of said track relay.

1. In combination, two successive sections ofrailway track, a track circuit for each section lncluding a'track relay, and a line, cirdicates proceed thecircuit is closed only if the track relay is energized.

6. In combination, two successive sections of railway track, a track circuit for each section includin a trackrelay, a signal for the advance section controlled by the track relay for suchsection, and a line circuit including the two rails of the rear section in multiple, said latter circuit being controlled by a front contactof the track relay for the advance sectionand by a contact operated by said signal and closed only when the signal gives a proceed indication. V

7. In combination, a section of railway track provided with a track relay havinga track winding and a local winding, a line circuit for said section controlled by a back contact of said track relay, and a circuitfor said local winding controlled by a front con tact of said track relay. I c 8. In combination, a section of railway track provided with a track relay having a track windingand a local winding, a signal controlled by said relay,means for controlling said local winding by said signal and bysaid relay, and a line circuit for said sec tion controlled by a back contact of said relay. 7

9. In combination, a section of railway track provided with a track relay, a'signal' controlled by said track relay, a line circuit for said section, and means including only said track relay and a circuit controller operated by said signal for detecting false energization of said track relay by line circuit current. I V

'. In testimony whereof I affix my signature. V

RONALD A. MCGANN. 

